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<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>事件练习：封装兼容性添加、删除事件的函数</title>
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pre{color:green;padding:10px 15px;background:#f0f0f0;border:1px dotted #333;font:12px/1.5 Courier New;}
span{color:#999;}
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<script type="text/javascript">
var EventUtil = {
	addHandler: function (oElement, sEvent, fnHandler) {
		oElement.addEventListener ? oElement.addEventListener(sEvent, fnHandler, false) : oElement.attachEvent("on" + sEvent, fnHandler)	
	},
	removeHandler: function (oElement, sEvent, fnHandler) {
		oElement.removeEventListener ? oElement.removeEventListener(sEvent, fnHandler, false) : oElement.detachEvent("on" + sEvent, fnHandler)
	},
	addLoadHandler: function (fnHandler) {
		this.addHandler(window, "load", fnHandler)
	}
};
EventUtil.addLoadHandler(function () {
	var aBtn = document.getElementsByTagName("input");
	
	//为第一个按钮添加绑定事件
	EventUtil.addHandler(aBtn[1], "click", function () {
		EventUtil.addHandler(aBtn[0], "click", fnHandler);	
		aBtn[0].value = "我可以点击了";
	});
	
	//解除第一个按钮的绑定事件
	EventUtil.addHandler(aBtn[2], "click", function () {
		EventUtil.removeHandler(aBtn[0], "click", fnHandler);
		aBtn[0].value = "毫无用处的按钮";	
	});
	
	//事件处理函数
	function fnHandler ()
	{
		alert("事件绑定成功！");	
	}	
})
</script>
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<pre>
&lt;script type="text/javascript"&gt;
var EventUtil = {
	addHandler: function (oElement, sEvent, fnHandler) {
		oElement.addEventListener ? oElement.addEventListener(sEvent, fnHandler, false) : oElement.attachEvent("on" + sEvent, fnHandler)	
	},
	removeHandler: function (oElement, sEvent, fnHandler) {
		oElement.removeEventListener ? oElement.removeEventListener(sEvent, fnHandler, false) : oElement.detachEvent("on" + sEvent, fnHandler)
	},
	addLoadHandler: function (fnHandler) {
		this.addHandler(window, "load", fnHandler)
	}
}
&lt;/script&gt;
</pre>
<center><input type="button" value="毫无用处的按钮"> <input type="button" value="绑定click"> <input type="button" value="解除绑定"></center>
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